BOISE - When allegations erupted that two Idaho lawmakers were caught in an affair earlier this summer, many supporters were quick to call their actions a mistake and not a crime.
However, in Idaho, adultery has been considered a felony since 1972. The crime is rarely prosecuted, but it remains on the books as a relic of America's long history of regulating sexual activity inside marriage.
There's no statewide data on how often adultery charges are filed, and it isn't included in Idaho State Police's annual state crime report.
Elizabeth Brandt, a law professor at the University of Idaho, says that adultery has historically been criminalized as a way to control the public's behavior. Today, Brandt says adultery is no longer seen as a threat.
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